Concurrent Sessions C: Fish Screening At Water Diversions I - Design of Large Cylindrical Fish Screen for the USBR Lower Yellowstone Project

The Lower Yellowstone Irrigation District diverts up to 1400 cfs into its main canal system on the lower Yellowstone River in Northeastern Montana. In late 2010, as part of a pallid sturgeon recovery program, the USBR and USACE began construction of a new state-of-the-art screened canal head works structure. After over 100 years of unscreened operations, the new fish screened facility was opened in spring 2012. The head works will be integrated into a major river gradient fish passage facility being proposed for construction soon. When completed, the new passage and protection facilities will reduce fish entrainment and open an additional 165 miles of river habitat for the endangered and native fishes. The new headwork facility’s fish protection system consists of twelve, 6.5-foot diameter and 25 feet long cylindrical fish protection screens. Each screen is designed to seal over the intake’s submerged sluice gates spaced along the 350-foot long riverbank facility. An integrated and flush-mounted track system was built into the vertical concrete walls to raise the screens in the non-irrigation season for protection from the significant ice and flood flows common on the river. When the 71-mile long irrigation canal is operational, each screen is lowered into position and an automatic brush cleaning system is used to keep the 1.75 mm wedge wire slots from clogging. The new intake facility was physically modeled at the USBR Hydraulics Lab along with several river fish passage options. The on-river screen design keeps the fish and debris in the river as opposed to traditional off-river screen designs with fish bypass facilities. The cylindrical design also reduced the facility footprint and allows diversions to occur over the river’s wide-ranging water surface fluctuations. This presentation will focus on the design, construction, and hydraulics of the intake screen facility, as well as the initial season’s operational experiences